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The tire pattern structure has a serious influence on automobile performance. In order to improve the tire performance, the strain energy density of tire tread under different working conditions was analyzed. The finite element model of longitudinal groove pattern of automobile tire was established to analyze the strain energy density under different working conditions, and the influence of parameter changes on the strain energy density of tire on dry road and slippery road was analyzed respectively. The multi-objective optimization model was established based on the finite element analysis results, and the function constraint conditions were set. Differential evolution method (DE) and non-dominated sorting genetic optimization method (NSGA-II) are used to design a multi-objective optimization program, which can quickly determine the optimization scheme after the input data. The finite element model was modified according to the optimization scheme and the strain energy density was analyzed. The results show that the performance of the optimized tire is greatly improved. The combination of finite element analysis technology and multi-objective optimization method can effectively reduce a lot of manpower, material resources and financial resources in mechanical product structure optimization. [ABSTRACT FROM AUTHOR]

Schiff base compounds and their metal complexes have become important synthetic organic drugs due to their extensive biological activities, which include anticancer, antibacterial and antiviral effects. In this study, we investigated the cytotoxic and apoptotic effects of VALD-3, a Schiff base ligand synthesized from o-vanillin derivatives, on human breast cancer cells and the possible underlying mechanisms. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)-test was used to observe the proliferation of human breast cancer MCF-7 and MDA-MB-231 cells induced by VALD-3. Flow cytometry analysis showed that VALD-3 triggered cell cycle arrest and induced apoptosis of breast cancer cells. Western blot analysis revealed that VALD-3 upregulated pro-apoptotic proteins (Bad and Bax), downregulated anti-apoptotic proteins (Bcl-2, Bcl-xl, survivin and XIAP) and increased the expression of cleaved caspase-3, cleaved caspase-8, Cyto-c and cleaved PARP. VALD-3 also regulated the Wnt/β-catenin signaling pathway in breast cancer cells, inhibiting the activation of downstream molecules. By xenografting human breast cancer cells into nude mice, we found that VALD-3 significantly suppressed tumor cell growth while showing low toxicity against major organs. In addition, survival analysis showed that VALD-3 can significantly prolong the survival time of mice (P = 0.036). This study is the first to show that VALD-3 induces apoptosis and cell cycle arrest in human breast cancer cells by suppressing Wnt/β-catenin signaling, indicating that it could be a potential drug for the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

Hyperuricemia contributes to chronic kidney disease development. However, it has been historically viewed with limited research interest. In this study, we mimicked the development of hyperuricemic nephropathy by using a potassium oxonate‐induced hyperuricemia rat model. We found that administering vitamin C at 10 mg/kg/day effectively ameliorated hyperuricemic nephropathy. Compared to the control group, rats with hyperuricemia had significantly increased serum uric acid level, xanthine oxidase activity, and urine microalbumin level, by 5‐fold, 1.5‐fold, and 4‐fold, respectively. At the same time, vitamin C supplementation reverted these values by 20% for serum uric acid level and xanthine oxidase activity and 50% for microalbumin level. Vitamin C also alleviated renal pathology and decreased the expression of pro‐inflammatory and pro‐fibrotic markers. A further mechanistic study suggested that vitamin C might attenuate hyperuricemic nephropathy in renal tubular epithelial cells induced by monosodium urate (MSU) crystal, at least in part, by directly inhibiting IL‐6/JAK2/STAT3 signaling pathway. Meanwhile, in macrophages, vitamin C inhibited the expression of TGF‐β, and reduced ROS level induced by MSU by about 35%. In short, our results suggest that vitamin C supplementation delay the progression of hyperuricemic nephropathy. [ABSTRACT FROM AUTHOR]

: Xanthine oxidoreductase (XOR) serves as the primary source of hydrogen peroxide and superoxide anions in the intestinal mucosa. However, its specific contribution to the progression of colonic disease remains unclear. In this study, we investigated the role of XOR in ulcerative colitis (UC) and attempted to identify the underlying mechanisms. We used the dextran sulfate sodium (DSS)–induced mouse model to mimic UC and observed that XOR inhibitors, allopurinol and diphenyleneiodonium sulfate (DPI), significantly alleviated UC in mice. In addition, treatment with cobalt chloride (CoCl2) and 1% O2 increased the expression of XOR and induced DNA oxidative damage in colonic epithelial cells. Furthermore, we identified that XOR accumulation in the nucleus may directly cause DNA oxidative damage and regulates HIF1α protein levels. In addition, allopurinol effectively protected colon epithelial cells from CoCl2-induced DNA damage. Altogether, our data provided evidence that XOR could induce DNA damage under hypoxic conditions, indicating a significant role of XOR in the initiation and early development of colitis-associated colorectal cancer (CAC). [ABSTRACT FROM AUTHOR]

Porous polymeric foams as dielectric layer for highly sensitive capacitive based pressure sensors have been extensively explored owing to their excellent flexibility and elasticity. Despite intensive efforts, most of previously reported porous polymer foams still suffer from difficulty in further lowering the attainable density limit of ≈0.1 g cm−3 while retaining high sensitivity and compressibility due to the limitations on existing fabrication techniques and materials. Herein, utilizing 3D interconnected networks of few‐layer hexagonal boron nitride foams (h‐BNFs) as supporting frameworks, lightweight and highly porous BN/polydimethylsiloxane composite foams (BNF@PDMS) with densities reaching as low as 15 mg cm−3 and permittivity close to that of air are fabricated. This is the lightest PDMS‐based foam reported to date. Owing to the synergistic effects between BN and PDMS, these lightweight composite foams possess excellent mechanical resilience, extremely high compressibility (up to 95% strain), good cyclic performance, and superelasticity. Being electrically nonconductive, the potential application of BNF@PDMS as a dielectric layer for capacitive sensors is further demonstrated. Remarkably, the as‐fabricated device can perform multiple sensing functions such as noncontact touch sensor, environmental monitoring sensor, and high sensitivity pressure sensor that can detect extremely low pressures of below 1 Pa. [ABSTRACT FROM AUTHOR]

Mitotically-associated long non-coding RNA (MANCR) is involved in malignant breast cancer. The present study analyzed the role of MANCR in hepatocellular carcinoma (HCC). MANCR was found to be upregulated in HCC and high expression level of MANCR in cancer tissues predicted poor survival of HCC patients. MicroRNA (miR)-122a was downregulated HCC and was inversely correlated with MANCR only in cancer tissues. MANCR overexpression resulted in downregulation of miR-122a, while miR-122a overexpression showed no obvious effects on MANCR expression. MANCR overexpression showed no significant effects on HCC cell proliferation but led to promoted cell migration and invasion. miR-122a overexpression led to inhibited migration and invasion of HCC cells and attenuated the effects of MANCR overexpression. Therefore, lncRNA MANCR may promote cancer cell proliferation in HCC by downregulating miR-122a. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the current study was to investigate whether the maximum standardized uptake value (SUVmax) measured by 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) could discriminate between aggressive and indolent non-Hodgkin lymphomas (NHLs) and correlations between the SUVmax and clinical variables and serum biochemical indicators in adult lymphoma.Methods: A total of 103 patients with lymphoma confirmed by biopsy, pretreatment 18F-FDG PET/CT scans, and a complete medical record were retrospectively enrolled in the study. Clinical variables that were evaluated included stage, pathological subtype, International Prognostic Index (IPI) score, and Ki-67 index, as well as serum biochemical indicators (e.g., lactate dehydrogenase [LDH] and erythrocyte sedimentation rate [ESR]) and metabolic parameters (e.g., SUVmax of the biopsy site on PET/CT). Correlations between SUVmax and clinical variables and serum biochemical indicators were investigated.Results: Of the 103 patients, 84 had NHL and 19 had Hodgkin lymphoma. The area under the receiver operating characteristic curve for examining the accuracy of SUVmax with regard to distinguishing between aggressive and indolent NHLs was 0.94 (95% confidence interval: 0.89-0.99), suggesting that SUVmax was a useful predictor of diagnosis. A cutoff value of 8.5 yielded a sensitivity of 76.3% and specificity of 92.0%. The SUVmax mean ± standard deviation of NHL (9.8 ± 6.0, range: 1.8-28.1) was higher than that of HL (7.5 ± 2.8, range: 3.5-13.9) (P = 0.016), but there was no statistically significant difference in SUVmax between NHL and HL (P > 0.05). SUVmax of the biopsy site was strongly positively correlated with Ki-67 index (r = 0.813, P < 0.001) and moderately positively correlated with IPI score (r = 0.332, P = 0.002), but it was not significantly correlated with clinical stage, LDH, or ESR (P > 0.05).Conclusions: 18F-FDG PET/CT may yield reliable measurements of tumor proliferation, and an SUVmax >8.5 may distinguish between aggressive and indolent NHLs. In adults with newly diagnosed lymphoma, SUVmax correlates with Ki-67 index and IPI score. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the value of real-time contrast-enhanced ultrasound in differential diagnosis of malignant liver tumors. Sixty patients pathologically diagnosed with liver cancer from May 2016 to May 2017 were selected as the subjects. All patients received ultrasonic diagnosis followed by the observation on dynamic contrast enhancement of the image and the analysis on perfusion characteristics and difference in contrast-enhanced ultrasound results in patients with different types of liver cancer. The signal during the arterial phase of 21 patients with well-differentiated hepatocellular carcinoma increased, including 12 cases of slow withdrawal of portal venous phase. The relative height of artery of 30 patients with middle-low differentiation of hepatocellular carcinoma increased along with the speed at which the contrast media was washed out at the end of the portal phase. In 9 patients with intrahepatic bile duct cancer, the enhancement of the arteries was slightly increased in the periphery of the tumor and low enhancement was found in the portal venous phase. There were some differences in the timing and the intensity of the enhancement of the ultrasound signals with 3 different types of diseases (P < 0.05). There are obvious differences in real-time contrast-enhanced ultrasound features of patients with different types of malignant liver tumor, which may provide references for clinical diagnosis. [ABSTRACT FROM AUTHOR]

Effective signal amplification is necessary for the sensitive detection of low-abundance proteins. In this work, a sandwich-type immunosensor for the sensitive detection of alpha-fetoprotein (AFP) was prepared. Hollow mesoporous silica spheres (HMSS) with a large specific surface area and loading capacity were synthesized. Next, their adsorption performance was improved by a hyaluronic acid (HA) coating that could inhibit the escape of lead(II) ions adsorbed on the hollow silica spheres. After that, an "off–on" strategy was applied to the immunosensor to amplify δ I. The sensitive detection of AFP was obtained by square wave voltammetry (SWV). The antifouling material (HA) not only reduces non-specific binding, but also has good biocompatibility and increases the number of attached secondary antibodies. Finally, we confirmed the successful application of the "off–on" strategy by some electrochemical tests. The final electrochemical sensor has high sensitivity and a low detection limit of 9.9 fg mL−1 (S/N = 3). The proposed "metal ion (organic small molecule)-HMSS@HA" bioresponsive release system has potential application value as a carrier for other electroactive substances. [ABSTRACT FROM AUTHOR]

Abstract: Wafer‐scale vertically aligned carbon nanotube/poly(vinyl alcohol) (VACNT/PVA) hydrogels are fabricated by infiltration of PVA among VACNTs and subsequent in situ hydrogelation. Owing to the homogeneous PVA infiltration, uniform distribution and orientation of the carbon nanotubes (CNTs) are well retained, which in turn provide large CNT‐PVA interfaces throughout the resulting hydrogels. Compared to bare PVA hydrogels, such composite hydrogels perform significantly enhanced longitudinal compressive responses upon both static and dynamic loadings, achieving improvements of up to 25.2‐ and 9.0‐fold in strength and loss modulus, respectively. The novel scalable fabrication of VACNT/PVA hydrogels and their attractive performances hold great potential for a wide range of applications. [ABSTRACT FROM AUTHOR]

A series of Pb(Zr 1-x Ti x )O 3 multilayer films alternatively stacked by Pb(Zr 0.52 Ti 0.48 )O 3 and Pb(Zr 0.35 Ti 0.65 )O 3 layers have been deposited on corning glass by magnetron sputtering. The films demonstrate pure perovskite structure and good crystallinity. A large tetragonality ( c / a ) of ∼1.061 and a shift of ∼0.08 eV for optical bandgap were investigated at layer engineered films. In addition, these samples exhibited a wild tunable electro-optic behavior from tens to ∼250.2 pm/V, as well as fast switching time of down to a few microseconds. The giant EO coefficient was attribute the strain-polarization coupling effect and also comparable to that of epitaxial (001) single crystal PZT thin films. The combination of high transparency, large EO effect, fast switching time, and huge phase transition temperature in PZT-based thin films show the potential on electro-optics from laser to information telecommunication. [ABSTRACT FROM AUTHOR]

In this work, we report for the first time a simple approach to fabricate 3D reduced graphene oxide/boron nitride (rGO/BN) sponges with no additional chemical cross-linkers. Encouragingly, such sponge possesses higher compressibility and better recoverability in both air and organic solvents as compared to the bare rGO sponge. The as-prepared rGO/BN sponge also exhibits excellent water resistance and high oil absorption capability, achieving up to 170 times its own weight toward a wide range of environmental contaminants. Especially, the absorbed oil can be easily removed by the absorption–squeezing process which is cost effective and environmental friendly for oil collection. Most importantly, the underlying reasons for the remarkable mechanical properties, excellent oil absorption capabilities have been analysed and revealed in depth. These exceptional characteristics together with the ease of scalable synthesis make the as-prepared 3D rGO/BN sponge show many promising applications ranging from tissue engineering, sensors, catalysis, energy storage and conversion to environmental remediation. [ABSTRACT FROM AUTHOR]

An increasingly branched rolling circle amplification (IB-RCA) which contains a padlock probe (PP) and a structurally tailored molecular beacon (MB) was innovatively developed for highly sensitive detection of cancer gene, Kras gene codon 12. In this system, the PP can be circularized after hybridization with the precisely-matched target DNA, while the stem of MB can be also opened by target DNA, resulting in hybridization with the circularized PP to generate a long tandem single-stranded DNA (ssDNA) product. Since the MB is also designed to hybridize with ssDNA product, the newly-opened MBs are able to trigger the next RCA reactions, therapy producing branched rolling circle amplification (RCA) products and in turn leading to the increasingly branched RCA (IB-RCA). This alternately and continuously operates hybridization-based MB opening and opened MBs-triggered RCA. As a result, a great number of MBs are opened that is associated with a dramatically amplified fluorescent signal, enabling to quantify target DNA down to 100 fM. This sensing method demonstrates a new concept of IB-RCA amplification even in a simple way to efficiently transduce the fluorescence signal, accomplishing the highly sensitive and selective detection of cancer gene. [ABSTRACT FROM AUTHOR]

We designed a novel water soluble topological structure polymer-ferrocene- terminated hyperbranched polyurethane (HPU-Fc) with good water solubility. The redox behaviors and the electrochemical kinetics parameters of HPU-Fcs were explored by cyclic voltammetry (CV) according to electrochemical principle. The topological structure polymer was applied for the design and engineering of non-enzymatic glucose sensor. The designed sensor showed good response to glucose concentration with good stability, favorable accuracy and high selectivity. The electrode was also used to detect glucose in blood samples, and the glucose contents detected by the electrode were in good agreement with those from the hospital where a common automatic biochemical analyzer (HF240-300) was used. This finding makes HPU-Fc a promising biosensor for directly sensing glucose. [ABSTRACT FROM AUTHOR]

Emerging evidence indicates that microRNAs (miRNA, or miR) play vital roles in regulating osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). Elucidation of the molecular mechanisms that govern BMSCs osteogenic differentiation is of paramount importance for improving the treatment of bone-related diseases. In our current study, we investigated the role of miR-23a in BMSCs osteogenesis. Our results revealed that miR-23a was significantly downregulated during osteogenic differentiation. Overexpression of miR-23a inhibited osteogenic differentiation of hBMSCs in vitro , whereas downregulation of miR-23a enhanced the process. Target prediction analysis and dual luciferase reporter assays confirmed that low-density lipoprotein (LDL)-receptor-related protein 5 (LRP5) was a direct target of miR-23a. Furthermore, knockdown of LRP5 inhibited osteogenic differentiation of hBMSCs, similar to the effect observed in upregulation miR-23a. Our data indicate that miR-23a plays an inhibitory role in osteogenic differentiation of hBMSCs, which may act by targeting LRP5. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO)/boron nitride (BN) composite films were successfully fabricated by facile vacuum filtration and subsequent thermal treatment. Their morphology, structure and electrochemical performance were systematically characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. Importantly, the as-prepared rGO/BN composite film with a 2 wt.% BN content as binder-free anode material for lithium ion batteries (LIBs) exhibited a high reversible capacity of 278 mAh·g −1 at a high current density of 100 mA·g −1 , high rate capability, and high capacity retention over the first 200 cycles. The enhanced electrochemical performances of rGO/BN composite film are attributed to the unique structure and the synergistic effects between layered BN and graphene, which favored electrolyte penetration and buffered the volume expansion during the lithiation and delithiation process. In addition, this work not only provides a versatile strategy for fabrication of other graphene-based films, but also shows the potential promise of rGO/BN composite film for other energy storage devices. [ABSTRACT FROM AUTHOR]

Neuroblastoma (NB) patients harboring mutated ALK can be expected to potentially benefit from targeted therapy based on ALK tyrosine kinase inhibitor (TKI), such as crizotinib and ceritinib. However, the effect of the treatment varies with different individuals, although with the same genic changes. Axl receptor tyrosine kinase is expressed in a variety of human cancers, but little data are reported in NB, particularly in which carrying mutated ALK. In this study, we focus on the roles of Axl in ALK-mutated NB for investigating rational therapeutic strategy. We found that Axl is expressed in ALK-positive NB tissues and cell lines, and could be effectively activated by its ligand GAS6. Ligand-dependent Axl activation obviously rescued crizotinib-mediated suppression of cell proliferation in ALK-mutated NB cells. Genetic inhibition of Axl with specific small interfering RNA markedly increased the sensitivity of cells to ALK-TKIs. Furthermore, a small-molecule inhibitor of Axl significantly enhanced ALK-targeted therapy, as an increased frequency of apoptosis was observed in NB cells co-expressing ALK and Axl. Taken together, our results demonstrated that activation of Axl could lead to insensitivity to ALK inhibitors, and dual inhibition of ALK and Axl might be a potential therapeutic strategy against ALK-mutated NB. [ABSTRACT FROM AUTHOR]

Bone and fat cells share a common progenitor, stromal/mesenchymal stem cells (MSCs), that can differentiate into osteoblasts or adipocytes. Osteogenesis and adipogenesis of MSCs maintain homeostasis under physiological conditions. The disruption of this homeostasis leads to bone-related metabolic diseases. For instance, reduction in bone formation, which is usually accompanied by an increase in bone marrow adipogenesis, occurs with aging, immobility, or osteoporosis. Thus, it is crucial to gain an understanding of how osteogenic and adipogenic lineages of MSCs are regulated. Here, we present evidence that let-7 is a positive regulator of bone development. Using gain- and loss-of-function approaches, we demonstrate that let-7 markedly promotes osteogenesis and suppresses adipogenesis of MSCs in vitro. Moreover, let-7 could promote ectopic bone formation of MSCs in vivo. Subsequent studies further demonstrated that let-7's effects are mediated through the repression of high-mobility group AT-hook 2 (HMGA2) expression. RNAi depletion of HMGA2 could also enhance osteogenesis and repress adipogenesis. Overall, we found a novel role of let-7/HMGA2 axis in regulating the balance of osteogenesis and adipogenesis of MSCs. Thus, let-7 can be used as a novel therapeutic target for disorders that are associated with bone loss and adipocyte accumulation. [ABSTRACT FROM AUTHOR]

Highlights: [•] VO x /graphene hybrid materials were fabricated using a simple hydrothermal method. [•] The performance of VO x –n% GO-T is affected by GNS content and annealing temperature. [•] The VO x –7.4% GO-300 composite electrode shows superior capacitive properties. [•] The excellent performance is attributed to the improved dispersion and utilization. [Copyright &y& Elsevier]

Amine-functionalized mesoporous silica-supported copper catalysts SBA-15@amine–Cu and SBA-15@Oamine–Cu were prepared and proved to be efficient and reusable for homocoupling of terminal alkynes at room temperature with air as the oxidant. SBA-15@amine–Cu exhibited better recyclability than SBA-15@Oamine–Cu. The differences in the catalytic performances of the catalysts could be ascribed to catalyst structure and the interaction between copper and the supports. The as-prepared catalysts were systematically characterized by inductively coupled plasma atomic emission spectroscopy (ICP-AES), high resolution-transmission electron microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and nitrogen physical adsorption. The analysis indicated that the mesoporous structure of the materials was retained during the immobilization process. XPS results suggested that the as-prepared catalysts were not obtained by a simple physical adsorption of CuCl on the supports. It is noted that, for aliphatic alkynes, the catalytic activity of SBA-15@amine–Cu is even higher than that of the homogeneous copper catalytic system and that of some previously reported heterogeneous systems. [ABSTRACT FROM AUTHOR]

Abstract: A mesoporous silica SBA-15-supported palladium with spindle-like nitrogen donor groups, 1,4-diaza-bicyclo[2.2.2]octane, has been successfully prepared and applied for homocoupling of terminal alkynes. The catalyst exhibited very high activity for terminal alkynes carrying various substitution groups, yields ranging from 70% to 94%, with a significant advantage that air acted as the oxidant. It also showed good reusability, could be easily recovered through filtration and washing, and reused at least five times with virtually no evident loss of catalytic performance. Furthermore, it was also proved to be an effective and air-stable heterogeneous catalyst for Suzuki coupling of aryl halides (X=I, Br) with arylboronic acids. The catalyst was systematically characterized by elemental analysis, X-ray photoelectron spectroscopy, high-resolution transmission electron microscope, nitrogen physical adsorption, Brunauer–Emmett–Teller method and X-ray powder diffraction. The analyses indicated that the mesoporous structure of the materials was retained during the immobilization process. [Copyright &y& Elsevier]

Abstract: An amine-functionalized mesoporous silica SBA-15 supported palladium catalyst was prepared and characterized. For the first time, this supported palladium has been used as an efficient phosphine-free and reusable catalyst for the cross-coupling of haloalkynes with terminal alkynes. A variety of haloalkynes and aromatic/aliphatic terminal alkynes were selectively coupled to afford unsymmetrical 1,4-disubstituted 1,3-diynes in good yields. [Copyright &y& Elsevier]

Influence of microsphere--crosslinked ratio on the performance of crosslinked polymer microsphere was studied by dynamic light scattering experiments, scanning e-electron microscopy experiments, nuclear pore membrane filtrating experiments and core flooding experiments. The experimental results show that swelling microspheres sizes are different because of different hydration crosslinked ratio; the smaller the crosslinked ratio becomes, the looser microspheres structure is, the larger swelling multiple is. With he decrease of crosslinked ratio, the soft degree of microsphere increased, and the deformability of microsphere enhanced. The nuclear pore membrane filtrating experimental results show that the microspheres with moderate size and better deformability have better blocking ability. The core flooding experiments results further show that the microsphere with better deformability can easier access to the deep reservoir and occur closure. The field application test shows hat the polymer microsphere system can increase oil production and reduce water. [ABSTRACT FROM AUTHOR]

High-pressure vapor−liquid equilibrium data for the binary systems of ethyl butyrate (EB) + carbon dioxide and propylene carbonate (PC) + carbon dioxide were measured. The experimental pressure range was from (1.00 to 13.00) MPa and the temperature range from (313.0 to 373.0) K. Experimental results were correlated with the Peng−Robinson equation of state with the two-parameter van der Waals mixing rule. At the same time, the Henry’s coefficient and solution enthalpy and solution entropy of CO2during dissolution at different temperature were also calculated. [ABSTRACT FROM AUTHOR]

A recent paper in this journal, presented a novel method by topical application of growth factors in stimulating diabetic cutaneous wound healing that caught our attention. We believe that the experimental method in the article is efficient and creative, but it also has some controversies and shortcomings to be discussed. We noted that the authors used “Tegaderm” as a semiocclusive dressing film and stated that it exerted a “splinting effect” on the wound margins and controlled contraction. Indeed, the “Tegaderm” itself can serve as a dressing film to isolate the wound bed with outside environments while the “splinting effect” is mainly achieved by adding silicone splints around the wound. Considering the unique properties of silicone splints and “Tegaderm,” our experimental group propose an alternative method named “combined-suturing” technique that is not only suturing the silicone splints but also securing the “Tegaderm” around the wound. The specific reasons and operative procedures are explained in detail in this letter. [ABSTRACT FROM AUTHOR]

In addition to its pivotal role in purine metabolism, xanthine oxidoreductase (XOR) is one of the key enzymes involved in superoxide radical generation. Oxidative stress has been implicated in the etiology of colorectal cancer, but the contribution of XOR remains unclear. Here we investigated the role of XOR in colitis-associated colorectal cancer (CAC) and the underlying mechanisms. Using clinical samples, we demonstrated that XOR up-regulation was an early event in colonic carcinogenesis. Pharmacological inhibition of XOR effectively delayed the progression of CAC. Moreover, XOR activity positively correlated with tumor necrosis factor-alpha (TNFα) protein levels. Mechanistically, TNFα may activate XOR transcription via activator protein-1 and, thus, promote endogenous hydrogen peroxide generation, resulting in oxidative DNA damage in colon cancer cells. On the other hand, XOR may regulate the TNFα mRNA transcripts by mediating LPS-induced macrophage M1 polarization. Collectively, XOR promotes tumor development by programming the tumor microenvironment and stimulates CAC progression via DNA damage-induced genetic instability. [ABSTRACT FROM AUTHOR]

Vapor−liquid equilibrium data for the carbon monoxide + dimethyl carbonate, oxygen + dimethyl carbonate, and dimethyl ether + dimethyl carbonate systems were measured at 293 K, 313 K, 353 K, and 373 K and at elevated pressures up to 12.00 MPa. The measurements were carried out in a cylindrical autoclave with a moveable piston and an observation window. The experimental data were correlated using the Peng−Robinson−Stryjek−Vera equation of state (EOS) with the two-parameter van der Waals II mixing rule. [ABSTRACT FROM AUTHOR]

Objectives. Myocardial protection with ATP-sensitive potassium channel (KATP channel) openers is as effective as St. Thomas’ cardioplegia (StTCP) in adult rabbit hearts. This study compares the effectiveness of the KATP channel opener pinacidil to StTCP in protecting neonatal rabbit hearts exposed to global ischemia.Methods. Seventeen neonatal rabbit hearts (7–9 days old) perfused with Krebs-Henseleit buffer (KHB) on a Langendorff apparatus underwent 90 min of normothermic ischemia. Six (ischemia control) received no pretreatment before or during ischemia. Six others (pinacidil) received a 3-min infusion of 50 μM pinacidil in KHB without StTCP at the onset of ischemia. Five others (StTCP) received a 3-min infusion of StTCP at the onset of ischemia. After 60 min of KHB reperfusion, recovery of left ventricular (LV) performance and coronary flow (CF) were measured and compared to preischemia. A paired t test was used for comparison between drug-treated and untreated groups.Results. Pinacidil-treated hearts had significantly better recovery of left ventricular developed pressure (47 ± 3.8 mmHg vs 32 ± 2.5 mmHg, P < 0.05), contractility (+dP/dtmax; 885.4 ± 74 mmHg vs 643.7 ± 65 mmHg, P < 0.05), left ventricular end diastolic pressure (10.5 ± 0.9 mmHg vs 17.4 ± 1.2 mmHg P < 0.05), compliance (−dP/dtmax; 994.2 ± 86 mmHg vs 673.6 ± 69 mmHg, P < 0.05), and CF (5.9 ± 0.4 ml/min vs 4.2 ± 0.2 ml/min, P < 0.05) compared to ischemic control. StTCP only improved the recovery of −dP/dtmax (877.4 ± 73 mmHg/s vs 673.6 ± 69 mmHg/s, P < 0.05) and CF (5.7 ± 0.3 ml/min vs 4.2 ± 0.2 ml/min, P < 0.05) compared to control.Conclusions. Pinacidil pretreatment provided superior recovery of systolic performance compared to St. Thomas’ cardioplegia solution in neonatal hearts. Myocardial protection by pretreatment with the KATP channel opener pinacidil may be a new strategy for myocardial protection during pediatric cardiac surgery. [Copyright &y& Elsevier]

Stability of advanced functional materials subjected to extreme conditions involving ion bombardment, radiation, or reactive chemicals is crucial for diverse applications. Here we demonstrate the excellent stability of wafer-scale thin films of vertically aligned hexagonal BN nanosheets (hBNNS) exposed to high-energy ions and reactive atomic oxygen representative of extreme conditions in space exploration and other applications. The hBNNS are fabricated catalyst-free on wafer-scale silicon, stainless steel, copper and glass panels at a lower temperature of 400 °C by inductively coupled plasma (ICP) assisted chemical vapor deposition (CVD) and subsequently characterized. The resistance of BNNS to high-energy ions was tested by immersing the samples into the plasma plume at the anode of a 150 W Hall Effect Thruster with BNNS films facing Xenon ions, revealing that the etching rate of BNNS is 20 times less than for a single-crystalline silicon wafer. Additionally, using O2/Ar/H2 plasmas to simulate the low Earth orbit (LEO) environment, it is demonstrated that the simulated plasma had very weak influence on the hBNNS surface structure and thickness. These results validate the strong potential of BNNS films for applications as protective, thermally conductive and insulating layers for spacecrafts, electric plasma satellite thrusters and semiconductor optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this work, sulfur doped carbon nitride quantum dots (S-CNQDs) were prepared by one-pot copolymerization using melamine and thiourea as starting materials. The composite (g-C 3 N 4 /S-CNQDs), showing enlarged surface area, was fabricated by one-step in situ polymerization. The composites displayed much better photocatalytic activity than pristine g-C 3 N 4 in degradation of methyl orange (MO) under UV–visible light irradiation. The removal efficiency of MO reached by 94.3% under visible light (λ ​> ​420 ​nm) illumination within 80 ​min, whereas it was nearly 100% under UV–visible light (λ ​> ​350 ​nm) irradiation within 40 ​min. The enhanced photocatalytic activity of composites is attributed to the doping of S-CNQDs, which leads to higher separation of photo-generated electron-holes, extended visible light response and more active sites. Additionally, the potential mechanism of photocatalytic degradation on MO by g-C 3 N 4 /S-CNQDs was proposed. This work presented a simple way for constructing S-CNQDs-based g-C 3 N 4 catalyst. The g-C 3 N 4 /S-CNQDs composites were synthesized by a simple in situ polymerization for the first time, integrating synthesis and doping of S-CNQDs simultaneously. Additionally, the potential mechanism of photocatalytic degradation on MO by g-C 3 N 4 /S-CNQDs was proposed. Image 1 • Sulfur doped carbon nitride quantum dots were achieved by a bottom-up process. • The g-C 3 N 4 /S-CNQDs composites were obtained by one-step in situ polymerization. • The composites displayed much better photocatalytic activity than pristine g-C 3 N 4. • The potential mechanism of degradation on MO by g-C 3 N 4 /S-CNQDs was proposed. • A convenient pathway for polymer doped with non-metallic S-CNQDs was presented. [ABSTRACT FROM AUTHOR]

Abstract: MoS2 microspheres with nanorods were successfully synthesized by hydrothermal method at 240°C for 24h, employing sodium molybdate and L-cysteine as reactants. L-cysteine turned out to be served as both the sulfur source and the directing molecule in the formation of molybdenum disulfide nanostructures. The as-prepared MoS2 was characterized by X-ray power diffraction (XRD), X-ray photoelectron spectrum (XPS), field-emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FT-IR). FE-SEM images showed that the product was microspheres, consisting of nanorods with length of about 100nm. The possible formation mechanism was also discussed. The results indicated that MoO2 was the metastable phase and Na2MoO4·2H2O was converted to MoS2 via MoO2. [Copyright &y& Elsevier]

• LLE data at three temperatures for (water + 2-propanol + ethyl butyrate or n-pentyl acetate) systems were determined. • The LLE data were correlated by using the extended and modified UNIQUAC models. • The reliability of the experimental LLE data was verified by the Hand and Bachman equations. • Distribution coefficients and separation factors were compared with those of other extracting agents from the literatures. • Extraction performance of ethyl butyrate and n-pentyl acetate to extract 2-propanol from aqueous solutions was confirmed. (Liquid + liquid) equilibrium (LLE) data were determined for two ternary systems of (water + 2-propanol + ethyl butyrate) and (water + 2-propanol + n-pentyl acetate) at T = (293.15, 303.15 and 313.15) K under atmospheric pressure. The experimental data were correlated by the thermodynamic modified UNIQUAC and extended UNIQUAC models. The consistency of the experimental LLE data was further ascertained by applying Hand and Bachman equations. The extraction capability of ethyl butyrate and n-pentyl acetate was estimated by distribution coefficients and separation factors. The extraction efficiencies of ethyl butyrate and n-pentyl acetate were compared with those of other extraction agents such as isobutyl acetate, butyl acetate, butyl propionate and sec-butyl acetate. And extraction performance of ethyl butyrate and n-pentyl acetate in the extraction of 2-propanol from 2-propanol-water solutions was confirmed. [ABSTRACT FROM AUTHOR]

• Synthesis of peroxide steroidal derivatives with isatin/indole side chain. • Compounds 7g and 7l exhibited significant anti-proliferative activities. • Compound 7g induced HepG2 cell apoptosis, inhibited cycle progression and colony growth. A series of novel 5α, 8α-endoperoxide steroidal hybrid derivatives containing isatin or indole substituents on the C-17 side chain were synthesized and characterized. The preliminary anti-proliferative activity of the compounds against HepG2, MCF-7, HT-29 and HeLa cell lines were investigated. Compounds 7g and 7l displayed significant anti-proliferative activity in vitro against HepG2 and Hela cells, with IC 50 values lower than 8 μM. Furthermore, the biological functions of 7g were examined by flow cytometry and colony analysis. The results showed that 7g could induce HepG2 cell apoptosis, inhibited cell cycle progression, and colony growth. The studies indicated that structural modification at C-17 position could be a promising launch point for design steroidal anticancer agents. [ABSTRACT FROM AUTHOR]

Inspired by the significant bioactivity of ergosterol peroxide, we designed and synthesized four fluorescent coumarin and ergosterol peroxide conjugates 8a–d through the combination of ergosterol peroxide with 7-N,N-diethylamino coumarins fluorophore. The cytotoxicity of synthesized conjugates against three human cancer cells (HepG2, SK-Hep1, and MCF-7) was evaluated. The results of fluorescent imaging showed that the synthesized conjugates 8a–d localized and enriched mainly in mitochondria, leading to significantly enhanced cytotoxicity over ergosterol peroxide. Furthermore, the results of biological functions of 8d showed that it could suppress cell colony formation, invasion, and migration; induce G2/M phase arrest of HepG2 cells, and increase the intracellular ROS level. [ABSTRACT FROM AUTHOR]

Heteroatom doping in graphene leads to bandgap opening and tunable electronic, magnetic and optical properties, which are important for graphene-based electronics applications. In recent years, scalable growth of nitrogen-doped graphene (NG) by chemical vapor deposition (CVD) has been extensively studied because of its potential for practical applications. A phenomenon that occurs exclusively for CVD-grown NG films is the segregation of doping concentration. However, most studies to date are conducted using highly polycrystalline NG films comprising small grain sizes. It is still unknown whether dopant segregation occurs in single crystalline NG domains. Here, we used hexamethylenetetramine ((CH 2 ) 6 N 4 ) as a single-source solid precursor to grow hexagonal-shaped monolayer NG single crystals of ∼20 µm on Cu substrates. The NG single crystals exhibit discrete concentric hexagonal rings comprising N depleted regions as determined by Raman spectroscopy. Supported by scanning tunneling microscopy experiments, we propose that the segregation of N dopants is caused by a competing N attachment mechanism to either zigzag or Klein edges during growth; where the former should result in higher N concentration and the latter with lower N concentration. This work provides critical insights into the growth mechanism of CVD-grown NG and enables new opportunities to engineer the properties of graphene by fabrication of lateral heterostructures. [ABSTRACT FROM AUTHOR]

Clostridium difficile toxin B (cdtB) is a critical virulence factor characterized with potential cytotoxicity and pro-inflammatory activity. This study aims to investigate anti-tumor effects of cdtB on breast cancer development. Clostridium difficile strain was cultured and cdtB recombinant protein (rcdtB) was synthesized. Breast cancer cell line, MDA-MB-231, was divided into Normal control, rcdtB 50, 100, 200 and 400 ng/ml group in vitro . Mice were divided into Normal control and rcdtB treatment group (400 ng/ml) in vivo . 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay was performed to evaluate inhibitive effects of rcdtB on cell growth. Flow cytometry and transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) were employed to examine apoptosis in vitro and in vivo , respectively. Cell cycle distribution was analyzed by utilizing commercial kit. B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax) were examined using western blot. Inflammatory response was detected using haematoxylin and eosin (HE). Erythroblastic leukemia viral oncogene homolog 2 (C-erbB-2) and cyclooxygenase-2 (Cox-2) were examined using immunohistochemical and immunofluorescence assay, respectively. The results indicated that rcdtB significantly induced MDA-MB-231 death, inhibited growth and decreased S-phase cells compared to Normal control group ( P  < 0.05). rcdtB significantly induced early and late apoptosis, and decreased Bcl-2 levels compared to Normal control group ( P  < 0.05). rcdtB significantly inhibited cell migration compared to Normal control group ( P  < 0.05). rcdtB significantly inhibited tumor growth and activated inflammation of breast cancer model compared to Normal control group ( P  < 0.01). rcdtB significantly reduced C-erbB-2 and Cox-2 in tumor tissues compared to Normal control group ( P  < 0.01). In conclusion, rcdtB treatment inhibited tumor growth and induced apoptosis through inhibiting Bcl-2 expression, inflammatory responses, and activating C-erbB-2 and Cox-2 expression in breast cancer mouse model. [ABSTRACT FROM AUTHOR]

An abstract of the article "Mesoporous Silica-Supported Copper-Catalysts for Homocoupling Reaction of Terminal Alkynes at Room-Temperature" by Hongling Li, Min Yang, Xia Zhang, Liang Yan, Jing Li and Yanxing Qi is presented.

[Display omitted] • Cu-Mo 2 C as a signal indicator for dual-mode immunosensors. • The electrochemical response signal was amplify by modified Ti 3 C 2 -Au. • The detection range of the immunosensor is 1 fg/mL ∼ 40 ng/mL. • The sensors have a low detection limits (DPV: 0.33 fg/mL and CA: 1.67 fg/mL). A method for detecting of Carcinoembryonic antigen(CEA) with improved accuracy is urgently needed. In this work, a dual-mode immunosensor for accurate detection of CEA was fabricated, which used a Cu-doped Mo 2 C co-catalyst as an enhancer. Especially, Cu-doped Mo 2 C presents a strong different pulse voltammetry (DPV) signal for the electron transfer between Cu2+ and Cu+, without the addition of K 3 [Fe(CN 6)] and other electron transfer mediators, but also shows high electrocatalytic activity towards H 2 O 2 redox reactions. So that detection sensitivity of the chronoamperometry (CA) was enhanced. Furthermore, characterized by excellent conductivity, highly ordered pore distribution and great surface area, Ti 3 C 2 Mxenes can be effective in promoting electron transfer and loading a large number of AuNPs. In the meantime, AuNPs can also immobilize CEA-Ab 1 through Au-N bonds. Based on a Cu-Mo 2 C-Au dual-signal indicator, Ti 3 C 2 Mxene-Au as the matrix, the immunsosensor was developed to achieve dual-signal detection of CEA. Satisfactory detection ranges (1 fg.mL−1 to 40 ng.mL−1) were obtained with limits of detection of 0.33 fg.ml −1 (DPV) and 1.67 fg.ml−1 (CA), respectively. Therefore, the prepared electrochemical immunosensor has good application prospects for the detection of CEA. [ABSTRACT FROM AUTHOR]

In the present study, we proposed a novel dual-cyclical nucleic acid strand-displacement polymerization (dual-CNDP) based signal amplification system for highly sensitive determination of tumor suppressor genes. The system primarily consisted of a signaling hairpin probe (SHP), a label-free hairpin probe (LHP) and an initiating primer (IP). The presence of target DNA was able to induce one CNDP through continuous process of ligation, polymerization and nicking, leading to extensively accumulation of two nicked triggers (NT1 and NT2). Intriguingly, the NT1 could directly hybridize SHP, while the NT2 could act as the target analog to induce another CNDP. The resulting dual-CNDP contributed the striking signal amplification, and only a very weak blank noise existed since the ligation template of target was not involved. In this case, the target could be detected in a wide linear range (5 orders of magnitude), and a low detection limit (78 fM) was obtained, which is superior to most of the existing fluorescent methods. Moreover, the dual-CNDP sensing system provided a high selectivity towards target DNA against mismatched target and was successfully applied to analysis of target gene extracted from cancer cells or in human serum-contained samples, indicating its great potential for practical applications. [ABSTRACT FROM AUTHOR]

BACKGROUND: Transcranial direct current stimulation (tDCS) has a considerable advantage in the rehabilitation treatment of dysphagia. OBJECTIVE: The purpose of this study was to explore the effect of tDCS combined with respiratory training on dysphagia in post-stroke patients. METHODS: From December 2017 to January 2019, 64 post-stroke patients who were hospitalized in the Department of Neurology of the Second Hospital of Hebei Medical University were enrolled in this study. They were randomly divided into control and treatment groups (n = 32). Patients in the two groups received routine swallowing rehabilitation training and respiratory training. On this basis, the patients in the treatment group received tDCS. The anode was placed in the movement area of the pharyngeal cortex on the unaffected side of the patients' bodies, and the cathode was placed in the upper orbital orbit on the opposite side. The current intensity was 1.5 mA, 20 min/time, 1 time/d, and 6 d/w. Before and after the treatment, the water swallow text, functional oral intake scale (FOIS), forced vital capacity (FVC) and peak expiratory flow (PEF) were assessed, and the correlation among them was evaluated. RESULTS: There were no differences in all indexes before and after treatment. After treatment, water swallow text, FOIS, FVC and PEF were all better than before treatment, and the clinical efficacy in the treatment group was significantly better than that in the control group. FVC and PEF were positively correlated with water swallow text and FOIS. CONCLUSION: tDCS combined with respiratory training may have a significant therapeutic effect on dysphagia in post-stroke patients. [ABSTRACT FROM AUTHOR]

Occupational exposure to trichloroethylene (TCE) causes a systemic skin disorder with hepatitis known as TCE hypersensitivity syndrome (TCE-HS). Human Leukocyte Antigen (HLA)-B*13:01 is its susceptibility factor; however, the immunological pathogenesis of TCE-HS remains unknown. We herein examined the hypothesis that autoantibodies to CYP2E1 are primarily involved in TCE-HS. A case–control study of 80 TCE-HS patients, 186 TCE-tolerant controls (TCE-TC), and 71 TCE-nonexposed controls (TCE-nonEC) was conducted to measure their serum anti-CYP2E1 antibody (IgG) levels. The effects of TCE exposure indices, such as 8-h time-weighted-average (TWA) airborne concentrations, urinary metabolite concentrations, and TCE usage duration; sex; smoking and drinking habits; and alanine aminotransferase (ALT) levels on the antibody levels were also analyzed in the two control groups. There were significant differences in anti-CYP2E1 antibody levels among the three groups: TCE-TC > TCE-HS patients > TCE-nonEC. Antibody levels were not different between HLA-B*13:01 carriers and noncarriers in TCE-HS patients and TCE-TC. The serum CYP2E1 measurement suggested increased immunocomplex levels only in patients with TCE-HS. Multiple regression analysis for the two control groups showed that the antibody levels were significantly higher by the TCE exposure. Women had higher antibody levels than men; however, smoking, drinking, and ALT levels did not affect the anti-CYP2E1 antibody levels. Anti-CYP2E1 antibodies were elevated at concentrations lower than the TWA concentration of 2.5 ppm for TCE exposure. Since HLA-B*13:01 polymorphism was not involved in the autoantibody levels, the possible mechanism underlying the pathogenesis of TCE-HS is that TCE exposure induces anti-CYP2E1 autoantibody production, and HLA-B*13:01 is involved in the development of TCE-HS. [ABSTRACT FROM AUTHOR]

Purpose: Exploring biomarkers for easy and reliable diagnosis of periprosthetic joint infection (PJI) has attracted an increasing attention. Coagulation parameters have been found to be associated with infections, but their role in diagnosing PJI is not well understood. The aim of this study was to explore the diagnostic value of coagulation parameters in PJI.Methods: We retrospectively recruited patients who underwent revision total hip arthroplasty (THA) and total knee arthroplasty (TKA) from January 2014 to December 2020. Patients were grouped into PJIs or non-PJIs, and PJIs were further divided into culture positive and culture negative groups. The diagnostic value of coagulation parameters including fibrin degradation product (FDP), D-dimer, platelet count (PC), and platelet count to mean platelet volume ratio (PVR) was evaluated by using receiver operating characteristic curve, in comparison with traditional biomarkers C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR).Results: A total of 186 patients including 136 THA and 50 TKA were studied. There were 105 PJI and 81 non-PJI patients. The coagulation parameters showed an inferior performance to CRP and ESR, with the area under the curve (AUC) of FDP, D-dimer, PC, PVR, CRP, and ESR being 0.805, 0.571, 0.703, 0.704, 0.882, and 0.824, respectively. The diagnostic performance of those coagulation parameters was similar in THA and TKA PJIs and was not superior to ESR or CRP in either culture-positive or culture-negative PJIs.Conclusion: Coagulation parameters FDP, D-dimer, PC, and PVR are of limited value for the diagnosis of periprosthetic joint infection in both THA and TKA patients. [ABSTRACT FROM AUTHOR]

To accomplish ultra-sensitive detection of alpha-fetoprotein(AFP), a novel electrochemical immunosensor using polydopamine-coated Fe3O4 nanoparticles (PDA@Fe3O4 NPs) as a smart label and polyaniline (PANI) and Au NPs as substrate materials has been created. The sensor has the following advantages over typical immunoassay technology: (1) The pH reaction causes PDA@Fe3O4 NPs to release Prussian blue (PB) prosoma while also destroying the secondary antibody label and immunological platform and lowering electrode impedance; (2) PB has a highly efficient catalytic effect on H2O2, allowing for the obvious amplification of electrical impulses; (3) PANI was electrodeposited on the electrode surface to avoid PB loss and signal leakage, which effectively absorbed and fixed PB while considerably increasing electron transmission efficiency. The sensor's detection limit was 0.254 pg·mL−1 (S/N = 3), with a detection range of 1 pg·mL−1 to 100 ng·mL−1. The sensor has a high level of selectivity, repeatability, and stability, and it is predicted to be utilized to detect AFP in real-world samples. [ABSTRACT FROM AUTHOR]

Low-density polyethylene (LDPE) was modified with 2-hydroxyethyl acrylate (HEA) by a swollen phase grafting method with azobisiso-butyronitrile (AIBN) as initiator and xylene as a swelling agent. Fourier transform infrared spectroscopy (FTIR) and1H-nuclear magnetic resonance (1H-NMR) showed that the HEA was grafted onto the PE molecular chains and the copolymer (LDPE-g-PHEA) was formed. The rheological data illustrated that the content of long chain branches (LCB) in LDPE-g-PHEA was higher than in LDPE. Melt flow index (MFI) measurements indicated that the LDPE backbone was degraded slightly when the HEA content was small in the process of grafting. X-ray diffraction (XRD) and water contact angle measurements demo-nstrated that the grafting degree had an influence on the crystallinity and polarity of the graft polymer. A staining analysis indicated that the dyeing of the product was improved continuously with increasing of the grafting degree. Polyvinylpyrrolidone (PVP), NaCl, and ultrasound were shown to contribute to the staining, with ultrasound being the most productive. The probable grafting reaction mechanism is pro-posed. The results of the influence of monomer concentration on the grafting reaction revealed that the grafting ratio and gel content of the product increased with increasing of HEA amount. [ABSTRACT FROM PUBLISHER]

As DNA is employed to serve as a smart building block, an increasing interest has been devoted to the development of different DNA-based machines for the specific purpose, for example, the exploration of inter- or intramolecular interaction. In the current contribution, we developed an intelligent DNA machine and its operation can be designed to execute the ultrasensitive colorimetric detection of target nucleic acids. The DNA machine consists of a hairpin probe (HP) and an assistant template (AT). Using p53 gene as the target model to trigger the molecular machine operation, cyclic nucleic acid strand displacement polymerization (CNDP) was specifically induced, leading to the DNAzyme mediated catalytic reaction for signal readout. Specifically, with the help of polymerase and nickase, one target molecule was able to drive DNA nano-mechanical devices one-by-one through the hybridization/polymerization displacement cycles, and every initiated machine continued to operate, causing the dramatic accumulation of G-quadruplex-contained products. The G-quadruplex structure after binding to hemin could act as a horseradish peroxidase (HRP)-mimicking DNAzyme and catalyzed the oxidation of 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) by H 2 O 2 . As a result, an enhanced color change could be detected because of the generation of oxidation product ABTS• + . In this way, the DNA machine has no any signal loss and enables the quantitative measurement of p53 DNA with a detection limit of 10 fM, indicating great promise for unique application in biomedical research and early clinical diagnosis. [ABSTRACT FROM AUTHOR]

Background: The Kingdom of Morocco approved BBIBP-CorV (Sinopharm) COVID-19 vaccine for emergency use on 22 January 2021 in a two-dose, three-to-four-week interval schedule. We conducted a retrospective cohort study to determine real-world BBIBP-CorV vaccine effectiveness (VE) against serious or critical hospitalization of individuals RT-PCR-positive for SARS-CoV-2 during the first five months of BBIBP-CorV use in Morocco. Methods: The study was conducted among adults 18–99 years old who were tested by RT-PCR for SARS-CoV-2 infection between 1 February and 30 June 2021. RT-PCR results were individually linked with outcomes from the COVID-19 severe or critical hospitalization dataset and with vaccination histories from the national vaccination registration system. Individuals with partial vaccination (< 2 weeks after dose two) or in receipt of any other COVID-19 vaccine were excluded. Unadjusted and adjusted VE estimates against hospitalization for serious or critical illness were made by comparing two-dose vaccinated and unvaccinated individuals in logistic regression models, calculated as (1-odds ratio) * 100%. Results: There were 348,190 individuals able to be matched across the three databases. Among these, 140,892 were fully vaccinated, 206,149 were unvaccinated, and 1,149 received homologous BBIBP-CorV booster doses. Unadjusted, full-series, unboosted BBIBP-CorV VE against hospitalization for serious or critical illness was 90.2% (95%CI: 87.8—92.0%). Full-series, unboosted VE, adjusted for age, sex, and calendar day of RT-PCR test, was 88.5% (95%CI: 85.8—90.7%). Calendar day- and sex-adjusted VE was 96.4% (95%CI: 94.6—97.6%) for individuals < 60 years, and was 53.3% (95%CI: 39.6—63.9%) for individuals 60 years and older. There were no serious or critical illnesses among BBIBP-CorV-boosted individuals. Conclusions: Effectiveness of Sinopharm's BBIBP-CorV was consistent with phase III clinical trial results. Two doses of BBIBP-CorV was highly protective against COVID-19-associated serious or critical hospitalization in working-age adults under real-world conditions and moderately effective in older adults. Booster dose vaccination was associated with complete protection, regardless of age, although only a small proportion of subjects received booster doses. [ABSTRACT FROM AUTHOR]

The early detection of tumour markers is essential for the timely treatment of cancer, and thus realising the sensitive detection of carcinoembryonic antigen (CEA) is significant. Herein, we employed an electrochemical immunosensor as a simple analytical method. The loading of precious metals significantly amplifies the signal of electrochemical immunosensors. In this study, the successful loading of Au NPs was achieved via the galvanic displacement method. Moreover, CuS nanoflowers possessed intrinsic peroxidase-like activity, which could catalyse the oxidation of o-phenylenediamine (OPD) to generate a light-orange product in the presence of hydrogen peroxide (H2O2). The flower-shaped CuS not only provided active sites for the catalytic reaction, but also possessed a large specific surface area, which could provide abundant sites for the placement of Au nanoparticles. Thus, it was suitable for the labelling of Ab2 for the sensitive detection of CEA. The instant current response (i–t) method detected CEA quantitatively, and the immunosensor prepared under the optimized conditions exhibited an excellent analytical performance. The detection range of the sensor prepared in this study was 0.1–80 ng mL−1 and its detection limit was 5.5 pg mL−1 (S/N = 3). [ABSTRACT FROM AUTHOR]

An ultra-sensitive electrochemical immunosensor for detecting carcinoembryonic antigen was prepared. Graphene oxide-gold was used as the substrate modifier of the sandwich immunosensor. The high conductivity of graphene oxide effectively enhanced the electron transfer rate. The large specific surface area of graphene and the biocompatibility of gold nanoparticles increased the number of primary antibodies. The bovine serum albumin coated silver – platinum composite was used as a secondary antibody tag to prepare signal probes. The excellent biocompatibility of bovine serum albumin increased the number of secondary antibody connections. Silver nanoparticles increased the speed of electron transfer, and platinum further enhanced electrochemical sensing capabilities by catalyzing hydrogen peroxide. The immunosensor showed good performance for detecting carcinoembryonic antigen. Under the optimal conditions, the dynamic response range for carcinoembryonic antigen was from 0.005 ng·mL−1 to 100 ng·mL−1 with a detection limit of 0.76 pg·mL−1. The immunosensor also shown high selectivity, suitable stability, and good reproducibility, which provides new capabilities for clinical carcinoembryonic antigen detection. [ABSTRACT FROM AUTHOR]

Highlights: [•] The two-stage gasification process proposed consists of FB pyrolyzer and fixed bed gasifier. [•] FB pyrolyzer operated at about 850°C and in O2 and steam-containing atmosphere. [•] Char bed layer can remove the tar in fuel gas effectively. [•] The pilot test fully verified the feasibility of two-stage gasification process. [ABSTRACT FROM AUTHOR]

In this study, the dual quenching mechanism of nitrogen-doped graphene quantum dots (NGODs) in Cu 2 S-MPA composites is deeply analyzed. On the one hand, the synergistic interaction of NGODs with Cu 2 S-MPA enhances the transfer of resonance energy between Cu 2 S-MPA and luminescent phenol, which makes the composite more quenching ECL stronger. On the other hand, the binding of NGODs to Cu+ promotes the reduction of Cu+ and reduces its adsorption of co-reactive reagents such as H 2 O 2 , which weakens the electrocatalytic activity of ROS and is detrimental to electron transfer, affecting the ECL efficiency. [Display omitted] • The problem that NGODs are highly water-soluble and cannot be used as markers was solved. • NGODs enhance the resonance energy transfer between Cu 2 S-MPA and luminol to achieve quenching. • Reduction of Cu 2 S by NDODs reduces electron transfer for ROS generation by modulating oxygen species adsorption. • The proposed ECL immunosensor exhibits excellent performance in terms of detection limit and detection range. This study explores the principles of resonance energy transfer and adsorption modulation using composites of Cu 2 S-MPA/NGODs. These composites can efficiently control the quenching process of electrochemiluminescence (ECL). Mercaptopropionic acid (MPA) was added during the synthesis of Cu 2 S-MPA to enhance its attachment to nitrogen-doped graphene quantum dots (NGODs). The UV absorption peaks of NGODs coincided with the emission peaks of luminol ECL, enabling resonance energy transfer and enhancing the quenching capability of Cu 2 S-MPA. Meanwhile, there is another quenching strategy. When the readily reducible Cu+ ions underwent partial reduction to Cu when they were bound to NGODs. This weakened the electrocatalytic effect on reactive oxygen species (ROS) and had a detrimental impact on electron transfer. Under optimal conditions, the immunosensor ECL intensity decreased linearly with the logarithm of carcinoembryonic antigen (CEA) concentration in the range of 0.00001–40 ng/mL, with a detection limit of 0.269 fg/mL. The sensor was effectively utilized for the identification of CEA in actual serum samples. [ABSTRACT FROM AUTHOR]